Steel alloy.



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ALBERT DE DION AND GEORGES BOUTON, OF PUTEAUX, FRANCE.

STEEL ALLGY.

no. ceases.

Specification of Letters Patent.

Patented Nov. ac, race.

Application filed August 15, 190%. 8erial No. 220,870,

Pieces, of which the following is a specifica-' tion.

This invention has for its object animproved steel containing nickel.

It is known that steels containing nickel are distributed in three groups'according to their microstructure. The first group is characterized by a pearlitic microstructure, the second one by a martensitic microstructure, and the third one by a olyhedrous microstructure. If to a steel containing nickel and having a pearlitic microstructure silicon in a proportion from 0.5 per cent. to two per cent. is added, the microstructure remains a pearlitic one; but the breaking load and the elastic limit is greatly increased, the striction, the lengthening, and the resistance to shocks being barely diminished. The following table compares, for instance, two types of these steels having a pearlitic microstructure and containing silicon with steels containing the same proportion oinickel and of carbon, but which do not contain silicon,

- these steels having been assayed after annealing at a temperature of 900 centigrade and slow cooling:

If to a steel having a martnsiticmicrm structure silicon in a proportion from 0.5 per cent. to three per cent. is added, the micromore than with the steels having a pearlitic microstructure, the fragility of the steel being not increased. Some of these steels have a breaking load which has not been obtained hitherto.

Elastic (larbon. v Nickel. Silicon. aggi 0.150 12 1.5 170 140 0.120 15 1 its 155 the same may be performed, we deciare that what We claim is- Asa new article of manufacture, a steel containing nickel, and an amonnt oi silicon in the proportion of (3.5 to three per cent. with. resoect to the steel.

n testimony whereof We have hereunto set our hands in presence of two subscribing Witnesses.

. ALBERT DE DIQN. GEORGES BQUTQN. Witnesses:

Hanson C. Conn, PIERRE Lnrso.

structure remains a n artensitic one; but the breaking load and elastic limit is increased 

